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Este problema se trata en esta pregunta Android: Wrong item checked when filtering listview. Para resumir el problema, al usar una vista de lista con un CursorAdapter y un filtro, los elementos seleccionados en una lista filtrada pierden su selección después de eliminar el filtro y, en su lugar, se seleccionan los elementos en esa posición en la lista no filtrada.Implementación de una vista de lista con selección múltiple con filtro utilizando un adaptador de cursor
Usando el ejemplo de código en la pregunta vinculada anterior, ¿dónde deberíamos poner el código para marcar las casillas de verificación? Creo que debería estar en el método getView() del CustomCursorAdapter, pero no estoy seguro. Además, ¿cómo accedemos al HashSet que contiene todos los Id seleccionados en la clase de adaptador personalizado, porque se inicializará y modificará en la actividad principal que contiene la lista?
Mi actividad aplicación del ListView
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.selectfriends);
Log.v(TAG, "onCreate called") ;
selectedIds = new ArrayList<String>() ;
selectedLines = new ArrayList<Integer>() ;
mDbHelper = new FriendsDbAdapter(this);
mDbHelper.open() ;
Log.v(TAG, "database opened") ;
Cursor c = mDbHelper.fetchAllFriends();
startManagingCursor(c);
Log.v(TAG, "fetchAllFriends Over") ;
String[] from = new String[] {mDbHelper.KEY_NAME};
int[] to = new int[] { R.id.text1 };
final ListView listView = getListView();
Log.d(TAG, "Got listView");
// Now initialize the adapter and set it to display using our row
adapter =
new FriendsSimpleCursorAdapter(this, R.layout.selectfriendsrow, c, from, to);
Log.d(TAG, "we have got an adapter");
// Initialize the filter-text box
//Code adapted from https://stackoverflow.com/questions/1737009/how-to-make-a-nice-looking-listview-filter-on-android
filterText = (EditText) findViewById(R.id.filtertext) ;
filterText.addTextChangedListener(filterTextWatcher) ;
/* Set the FilterQueryProvider, to run queries for choices
* that match the specified input.
* Code adapted from https://stackoverflow.com/questions/2002607/android-how-to-text-filter-a-listview-based-on-a-simplecursoradapter
*/
adapter.setFilterQueryProvider(new FilterQueryProvider() {
public Cursor runQuery(CharSequence constraint) {
// Search for friends whose names begin with the specified letters.
Log.v(TAG, "runQuery Constraint = " + constraint) ;
String selection = mDbHelper.KEY_NAME + " LIKE '%"+constraint+"%'";
mDbHelper.open();
Cursor c = mDbHelper.fetchFriendsWithSelection(
(constraint != null ? constraint.toString() : null));
return c;
}
});
setListAdapter(adapter);
Log.d(TAG, "setListAdapter worked") ;
listView.setItemsCanFocus(false);
listView.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
// listView.setOnItemClickListener(mListener);
Button btn;
btn = (Button)findViewById(R.id.buttondone);
mDbHelper.close();
}
@Override
protected void onListItemClick(ListView parent, View v, int position, long id) {
String item = (String) getListAdapter().getItem(position);
Toast.makeText(this, item + " selected", Toast.LENGTH_LONG).show();
//gets the Bookmark ID of selected position
Cursor cursor = (Cursor)parent.getItemAtPosition(position);
String bookmarkID = cursor.getString(0);
Log.d(TAG, "mListener -> bookmarkID = " + bookmarkID);
Log.d(TAG, "mListener -> position = " + position);
// boolean currentlyChecked = checkedStates.get(position);
// checkedStates.set(position, !currentlyChecked);
if (!selectedIds.contains(bookmarkID)) {
selectedIds.add(bookmarkID);
selectedLines.add(position);
} else {
selectedIds.remove(bookmarkID);
selectedLines.remove(position);
}
}
private TextWatcher filterTextWatcher = new TextWatcher() {
public void afterTextChanged(Editable s) {
}
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
public void onTextChanged(CharSequence s, int start, int before, int count) {
Log.v(TAG, "onTextChanged called. s = " + s);
adapter.getFilter().filter(s);
}
};
@Override
protected void onDestroy() {
super.onDestroy();
filterText.removeTextChangedListener(filterTextWatcher);
}
Mi adaptador cursor personalizado:
public class FriendsSimpleCursorAdapter extends SimpleCursorAdapter implements Filterable {
private static final String TAG = "FriendsSimpleCursorAdapter";
private final Context context ;
private final String[] values ;
private final int layout ;
private final Cursor cursor ;
static class ViewHolder {
public CheckedTextView checkedText ;
}
public FriendsSimpleCursorAdapter(Context context, int layout, Cursor c,
String[] from, int[] to) {
super(context, layout, c, from, to);
this.context = context ;
this.values = from ;
this.layout = layout ;
this.cursor = c ;
Log.d(TAG, "At the end of the constructor") ;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
Log.d(TAG, "At the start of rowView. position = " + position) ;
View rowView = convertView ;
if(rowView == null) {
Log.d(TAG, "rowView = null");
try {
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
rowView = inflater.inflate(layout, parent, false);
Log.d(TAG, "rowView inflated. rowView = " + rowView);
ViewHolder viewHolder = new ViewHolder() ;
viewHolder.checkedText = (CheckedTextView) rowView.findViewById(R.id.text1) ;
rowView.setTag(viewHolder);
}
catch (Exception e) {
Log.e(TAG, "exception = " + e);
}
}
ViewHolder holder = (ViewHolder) rowView.getTag();
int nameCol = cursor.getColumnIndex(FriendsDbAdapter.KEY_NAME) ;
String name = cursor.getString(nameCol);
holder.checkedText.setText(name);
Log.d(TAG, "At the end of rowView");
return rowView;
}
}
Según este enlace, http://codereview.stackexchange.com/questions/1057/android-custom-cursoradapter-design, es mejor que anulemos newView y bindView. – rohitmishra